diff --git a/tools/erc-repository-indexer/erc-contract-indexer/package-lock.json b/tools/erc-repository-indexer/erc-contract-indexer/package-lock.json
index c65c78b95..d99d7e2ff 100644
--- a/tools/erc-repository-indexer/erc-contract-indexer/package-lock.json
+++ b/tools/erc-repository-indexer/erc-contract-indexer/package-lock.json
@@ -9,9 +9,11 @@
       "version": "0.1.0",
       "license": "Apache-2.0",
       "dependencies": {
+        "@types/lodash": "^4.17.14",
         "ahocorasick": "^1.0.2",
         "dotenv": "^16.4.5",
-        "ethers": "^6.13.4"
+        "ethers": "^6.13.4",
+        "lodash": "^4.17.21"
       },
       "devDependencies": {
         "@hashgraph/sdk": "^2.55.0",
@@ -1775,6 +1777,12 @@
         "pretty-format": "^29.0.0"
       }
     },
+    "node_modules/@types/lodash": {
+      "version": "4.17.14",
+      "resolved": "https://registry.npmjs.org/@types/lodash/-/lodash-4.17.14.tgz",
+      "integrity": "sha512-jsxagdikDiDBeIRaPYtArcT8my4tN1og7MtMRquFT3XNA6axxyHDRUemqDz/taRDdOUn0GnGHRCuff4q48sW9A==",
+      "license": "MIT"
+    },
     "node_modules/@types/node": {
       "version": "22.10.1",
       "resolved": "https://registry.npmjs.org/@types/node/-/node-22.10.1.tgz",
@@ -4105,6 +4113,12 @@
         "node": ">=8"
       }
     },
+    "node_modules/lodash": {
+      "version": "4.17.21",
+      "resolved": "https://registry.npmjs.org/lodash/-/lodash-4.17.21.tgz",
+      "integrity": "sha512-v2kDEe57lecTulaDIuNTPy3Ry4gLGJ6Z1O3vE1krgXZNrsQ+LFTGHVxVjcXPs17LhbZVGedAJv8XZ1tvj5FvSg==",
+      "license": "MIT"
+    },
     "node_modules/lodash.camelcase": {
       "version": "4.3.0",
       "resolved": "https://registry.npmjs.org/lodash.camelcase/-/lodash.camelcase-4.3.0.tgz",
diff --git a/tools/erc-repository-indexer/erc-contract-indexer/package.json b/tools/erc-repository-indexer/erc-contract-indexer/package.json
index d4ad144d0..f5e5b4690 100644
--- a/tools/erc-repository-indexer/erc-contract-indexer/package.json
+++ b/tools/erc-repository-indexer/erc-contract-indexer/package.json
@@ -22,8 +22,10 @@
     "typescript": "^5.7.2"
   },
   "dependencies": {
+    "@types/lodash": "^4.17.14",
     "ahocorasick": "^1.0.2",
     "dotenv": "^16.4.5",
-    "ethers": "^6.13.4"
+    "ethers": "^6.13.4",
+    "lodash": "^4.17.21"
   }
 }
diff --git a/tools/erc-repository-indexer/erc-contract-indexer/src/services/registryGenerator.ts b/tools/erc-repository-indexer/erc-contract-indexer/src/services/registryGenerator.ts
index 3a6c66880..2768c5d45 100644
--- a/tools/erc-repository-indexer/erc-contract-indexer/src/services/registryGenerator.ts
+++ b/tools/erc-repository-indexer/erc-contract-indexer/src/services/registryGenerator.ts
@@ -23,6 +23,7 @@ import path from 'path';
 import constants from '../utils/constants';
 import { ERCOutputInterface } from '../schemas/ERCRegistrySchemas';
 import { Helper } from '../utils/helper';
+import _ from 'lodash';
 
 export class RegistryGenerator {
   /**
@@ -108,33 +109,47 @@ export class RegistryGenerator {
   }
 
   /**
-   * Updates a registry file with new contracts, removing duplicates if any.
-   * @param {string} filePath - Path to the registry file
-   * @param {ERCOutputInterface[]} newContracts - New contracts to add to registry
-   * @returns {Promise<void>} Promise that resolves when registry is updated
+   * Updates a registry file with new contracts by merging them with existing contracts,
+   * ensuring the registry remains sorted and free of duplicates.
+   *
+   * @param {string} filePath - The file path to the registry file.
+   * @param {ERCOutputInterface[]} newContracts - The new contracts to add to the registry.
+   * @returns {Promise<void>} - A promise that resolves once the registry is successfully updated.
+   *
    * @private
    */
   private async updateRegistry(
     filePath: string,
     newContracts: ERCOutputInterface[]
   ): Promise<void> {
+    let uniqueContracts: ERCOutputInterface[] = [];
     const fileContent = this.readContentsFromFile(filePath);
     const existingContracts = fileContent
       ? (JSON.parse(fileContent) as ERCOutputInterface[])
       : [];
 
-    // Create a Map to deduplicate contracts by contractId
-    const contractMap = new Map(
-      [...existingContracts, ...newContracts].map((contract) => [
-        contract.contractId,
-        contract,
-      ])
-    );
+    if (!existingContracts.length) {
+      uniqueContracts = newContracts;
+    } else if (
+      // Since both arrays are sorted in ascending order, if the `contractId` of the last item in `existingContracts`
+      // is less than the `contractId` of the first item in `newContracts`, just merged the contracts and remove dups without sorting.
+      existingContracts[existingContracts.length - 1].contractId <
+      newContracts[0].contractId
+    ) {
+      uniqueContracts = _.chain([...existingContracts, ...newContracts]) // merge contracts
+        .uniqBy('contractId') // Remove duplicates based on contractId
+        .value(); // Extract the final array
+    } else {
+      uniqueContracts = _.chain([...existingContracts, ...newContracts]) // merge contracts
+        .uniqBy('contractId') // Remove duplicates based on contractId
+        .sortBy((contract) => Number(contract.contractId.split('.')[2])) // Sort by the numeric value of contractId
+        .value(); // Extract the final array
+    }
+
+    await this.writeContentsToFile(filePath, uniqueContracts);
 
     // Convert Map values back to array for file writing
-    const uniqueContracts = Array.from(contractMap.values());
 
-    await this.writeContentsToFile(filePath, uniqueContracts);
     console.log(
       `Finished writing ${newContracts.length} new ERC token contracts to registry.`
     );
diff --git a/tools/erc-repository-indexer/erc-contract-indexer/src/utils/helper.ts b/tools/erc-repository-indexer/erc-contract-indexer/src/utils/helper.ts
index ec70325a2..c9f02d2d0 100644
--- a/tools/erc-repository-indexer/erc-contract-indexer/src/utils/helper.ts
+++ b/tools/erc-repository-indexer/erc-contract-indexer/src/utils/helper.ts
@@ -19,8 +19,8 @@
  */
 
 import axios, { AxiosInstance } from 'axios';
-import path from 'path';
 import constants from './constants';
+import path from 'path';
 
 export class Helper {
   /**